Hillary Clinton got a little testy Thursday with an NPR interviewer who questioned her motives in endorsing gay marriage after first opposing it.

NPR's Terry Gross repeatedly the former secretary of state, senator and first lady whether her opinion had changed or if the atmosphere had changed enough that she felt like she could express her opinion.

"You know I really, I have to say, I think you being very persistent, but you are playing with my words and playing with what is such an important issue," Clinton said.

“I’m just trying to clarify so I can understand," Gross responded.

“No, I don’t think you are trying to clarify," Clinton said. "I think you are trying to say that I used to be opposed and now I am in favor and I did it for political reasons. And that’s just flat wrong. So let me just state what I feel like I think you are implying and repudiate it. I have a strong record. I have a great commitment to this issue and I am proud of what I’ve done and the progress were making.”

Clinton had opposed gay marriage, but said she supported it in a video in 2013 after leaving the State Department following similar proclamations by President Barack Obama and Vice President Joe Biden.

Gross was interviewing Clinton about her memoir, Hard Choices, which was released on Tuesday.

Clinton said she will decide whether to run for president by the end of the year at the earliest. But the former first lady, U.S. senator from New York and top American diplomat is already the presumed front-runner for her party’s nomination in 2016.

A recording of the NPR interview was released by America Rising, a Republican group that focusing on Clinton in anticipation of her potential 2016 presidential run.